It's easy to fall in love with a friendly dog like Bear. Video clips provided by David Wexler's family show the one-year old Golden Retriever being petted and loved by the Wexlers. However, three days after Wexler adopted the dog from an area animal shelter, Bear became very sick.

"He started having symptoms where he was throwing up, drinking tons and tons of water and throwing it up. Vomiting. Diarrhea," Wexler told FOX 4 News on Thursday.

Wexler said Bear died as the family was rushing him to an emergency vet visit. He said it appeared the dog had been poisoned.

"Trying to tell your 12-year-old daughter the puppy we just got for your birthday died is one of the hardest things I've ever had to do," Wexler said.

The family said Bear was rarely out of their sight -- roaming either the backyard or inside the house.

Wexler said he believes someone poisoned the dog, perhaps by throwing poisoned food into his yard for the dog to ingest. He said the same thing happened to one of his neighbors when two of their dogs died under similar circumstances.

Wexler has read all about it on the social media platform Nextdoor, which has a series of posts from his Overland Park neighborhood. The posts are made by upset animal owners, many of whom say their dogs are either sick or they've already died from poisoning.

"It blows your mind that someone could be this heartless and cruel," Wexler said.

Stanley Veterinary Clinic posted a warning this week on Facebook, which says someone near the Deanna Rose Farmstead and the walking trails nearby may be leaving behind bits of food laced with rat poison.

Sean Riley, spokesperson for the city of Overland Park, said park caretakers aren't to blame, as they don't use poison of any kind. Deanna Rose Farmstead is also closed for the season and won't reopen until April 1.

"We haven't recovered any kind of rat poison at this time," Overland Park Police Officer John Lacy said Thursday.

Lacy, the department's public information officer, said his department hasn't seen a single confirmed case of dog poisoning. The Wexlers said their veterinarian found toxins in their dog's system, rather than poisons, and the toxins can come from other sources as well.

"We are urging the public that if you feel your dog has been poisoned, contact your veterinarian and also contact the police department at the same time," Lacy said.

FOX 4 News has covered a number of reports concerning poison dogs in recent weeks. Managers at the Stanley Veterinary Clinic remind dog owners to be careful while walking their dogs and to keep animals from eating random items they find in the great outdoors.